1. Field of the Invention
The present invention relates to a medical appliance for carrying a sheet-shaped therapeutic substance to an affected site and administering the same to the affected site.
2. Description of the Prior Art
In surgical operations for respiratory organ illnesses, a treatment in which a sheet-shaped (cloth-like) substance made of a biodegradable/bioabsorbable material such as polyglycolic acid is stuck to an organ to reinforce sutures or to prevent air from leaking from the sutures is often performed. Additionally, as shown in a non-patent publication entitled “ATTEMPT TO STOP INTRAOPERATIVE AIR LEAK BY A CELL SHEET” in the abstract journal of the third congress of the Japanese Society for Regenerative Medicine in 2003, and in a non-patent publication entitled “DYNAMIC SEALING OF LUNG AIR LEAKS BY THE TRANSPLANTATION OF TISSUE ENGINEERED CELL SHEETS” in the Biomaterials 28 (2007) 4294-4302, available online (http://www.elsevier.com/locate/biomaterials) from Jun. 28, 2007, a treatment technique in which autologous cells are cultured to be regenerated into a cell sheet which is transplanted onto an affected site has been proposed. In recent years, endoscopic operations have been widely carried out as minimally invasive operations, and endoscopic forceps have mainly been used for carrying and administering a therapeutic substance such as the aforementioned sheet-shaped substance.
However, to bring a sheet-shaped therapeutic substance, which is liable to be damaged and tends to stick to itself, to an affected site and then spread the sheet-shaped therapeutic substance in order to transplant the sheet-shaped therapeutic substance precisely to an affected site with the use of a forceps, an advanced technique is required and making an improvement to the workability of the transplanting has been desired. Under these circumstances, the assignee of the present patent application has proposed a medical appliance for carrying a sheet-shaped therapeutic substance to an affected site and administering the medical appliance to the affected site, which is disclosed in Japanese patent application No. 2007-10452. This medical appliance can make a resiliently deformable sheet supporting element thereof that supports a sheet-shaped therapeutic substance deformed between a flat unrolled shape and a tubular housed shape, and can also make a proximal end of the sheet supporting element perform a bending operation by variations in fluid pressure of a fluid supplied in the medical appliance.
Structurally, the therapeutic-substance carrying/administering appliance disclosed in the aforementioned Japanese patent application needs to be provided with minute fluid channels inside the sheet supporting element thereof, and the circulation of the fluid filled in the minute fluid channels needs to be strictly controlled, and accordingly, there is room to improve the production cost and the reliability of the appliance when it is in operation.